Reviews have been initiated by the Air Force, the Defense Department's inspector general and the undersecretary of defense for intelligence and security, the newspaper reported, citing eight people with knowledge of the rocket company and internal documents.

"Elon Musk and his rocket company, SpaceX, have repeatedly failed to comply with federal reporting protocols aimed at protecting state secrets, including by not providing some details of his meetings with foreign leaders," the Times report said.

The Times said the Air Force recently cited potential security risks in denying Musk high-level security access and that allies including Israel have flagged concerns he could share sensitive data.

Last month, two Democratic U.S. senators, Senator Jeanne Shaheen and Jack Reed, said reports that billionaire Elon Musk has held multiple calls with Russian officials, including President Vladimir Putin, should be investigated by the Pentagon and law-enforcement agencies on national security grounds.

Reports that billionaire Elon Musk has held multiple calls with Russian officials, including President Vladimir Putin, should be investigated by the Pentagon and law-enforcement agencies on national-security grounds, two senior Democratic senators said in a letter last month.

Air Force Secretary Frank Kendall responded last week to Shaheen that he shared those concerns but could not comment on the status of an person's security clearance.